Motion dampers are often used in the car industry in order to slow down the movement of an openable door, such as the door of a glove compartment. Such doors are often rather heavy and are designed such that a portion of the content of the glove compartment rests on them. When the lock of the door is released, the door swings downwardly into the open position under force. So that the door will not abruptly drop down and fall on the legs of the passenger, a hydraulic or pneumatic motion damper (DE 296 00 438 U1) is provided. The restrainer may consist of a cylinder closed at one side with a piston movable therein and a piston rod connected to the piston. The cylinder is pivotally mounted on a part of the motor vehicle, whereas the free end of the piston rod is connected to the door.
In order for the glove compartment to be illuminated during opening of the door, an interior light is mounted in it. A switch is connected to the motor vehicle in the one side of the door which has contact tongues that are pressed onto one another by two springs. A plastic operating member is either directly molded to the door or manufactured separately and connected to the door. When the door is closed, the operating member engages the contact tongues of the switch, interrupting the current supply to the interior light. Upon opening the door, the operating member is pulled out from between the contacts so that they will rest against one another, activating the interior light. Mounting the switch on the vehicle requires significant installation expense. When the operating member is directly molded to the door, a more complicated and more expensive injection mold is required. When separately manufactured, a separate injection mold is required. Furthermore the separately manufactured operating member must in addition be mounted on the door.
It has also been found that at high temperatures, such as those reached inside a vehicle in the summer, the door expands significantly, which causes the operating member to shift transversely with respect to the contact tongues. This can result in the operating member malfunctioning and damaging the contacts.
The European Patent Application EP 0 413 308 A2 discloses a motion restrainer having an integrated light source and a switch. The switch is formed out of two contact tongues, which, when the door is opened, are biased against one another, closing the circuit to the current supply of the light source. When closing the door, an operating member arranged on the cylinder housing of the motion restrainer engages between the contacts, thus breaking the circuit and turning off the light.
A disadvantage of a motion damper with this type of switch is that the initial tension of the contacts is not sufficient to press these contacts firmly against one another when strong vibrations or temperature changes occur. Thus, it is possible for contact breakdowns to occur in the case of strong motor vibrations.
Therefore the basic purpose of the invention is to provide a motion-damping arrangement, in particular for motor vehicles, of the abovementioned type, which is cheaper to manufacture and install, and operates safely.
Compared with the motion restrainer of the state of the art, the present invention has the advantage that the contact, when the door is open, is automatically closed by the operating member. This feature avoids contact breakdowns due to vibration and heat expansion. Furthermore the contacts are pressed against one another over the entire length of thrust of the motion damper so that for every open position of the door a safe contact is guaranteed.